Abstract: 3vol%（TiC +TiB）/Ti-6Al-4V composites were prepared by powder metallurgy. And the effects of aging temperature on the microstructure and mechanical properties of the composites were investigated. The results show that, when aging at 400-500 ℃, with the increase of aging temperature, the fine β phase precipitates increase, showing a dispersion distribution. When aging temperature increases to 550 ℃, the size of β phase becomes larger, resulting in the decline of mechanical properties. There are cleavage steps and a large number of river patterns at the tensile fracture, and holes left by TiB reinforcement fracture are found, which shows brittle fracture. When the aging process is 500 ℃×4 h（air cooling）, the composites have the best comprehensive properties, the tensile strength is 758.6 MPa and the elongation is 2.1%.